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United States Patent | 5,761,344 |
Al-Hussein | June 2, 1998 |
A personal imaging computer system, which is connectable to and operable with a computerized local or wide area network, identifies characters in a document on which the characters are formed. The system scans the document to obtain a gray-scale image of the document, de-skews the gray-scale image, generates a binary image from the de-skewed gray-scale image by comparing the gray-scale image with the threshold, segments the binary image to locate individual characters within the binary image and to determine the shape of the individual characters, extracts gray-scale image information from the gray-scale image for each such individual character based on the location and shape of the character in the binary image, recognition-processes the extracted gray scale image information to determine the identity of the character, and stores the identity of the character. Image pre-processing for the personal imaging computer system includes pre-processing for de-skewing the image, for obtaining and applying a global threshold which converts a gray-scale image to a binary image, for removing underlines from underlined characters in the image, for obtaining connected components within a binary image, and for applying plural sets of rules to the connected components so as to filter text-type connected components from non-text type connected components, whereby only text-type connected components are subjected to character recognition processing.
Inventors: | Al-Hussein; Hussein (Santa Clara, CA) |
Assignee: | Canon Kabushiki Kaisha (Tokyo, JP) |
Appl. No.: | 514001 |
Filed: | August 11, 1995 |
Current U.S. Class: | 382/237 |
Intern'l Class: | G06K 009/38 |
Field of Search: | 382/168,169,170,171,232,237,270,271,272,273,274 358/466,461 |
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5539843 | Jul., 1996 | Murakami et al. | 382/237. |
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